Drive mechanism for self-propelled implements



Sept. 30, 1958 w. F. EARLEY 2,

DRIVE MECHANISM FOR SELF-PROPELLED IMPLEMENTS- Original Filed July 23, 1954 2 Sheets-Sheet 1 n N N R \m mvzirron wilburFl-l'rarleg ATTORNEYS- 30,1958 w. F. EARLEY DRIVE MECHANISM FOR SELF-PROPELLED IMPLEMENTS 2 Sheets-Sheet '2 Original Filed July 23, 1954 R O T N r- V m ATTORNEYS DRIVE. MECHANISM FOR FSELF-PROPELIJED llVIPLEMENTS Wilbur FJ'Earley,"Stockton, C alif., assignor to Guntert -& Zimmerman 'C'onst."'Div.,'Inc., Stockton, Califi, a

corporation of California .This invention relates to self-propelled earth working implements such as ditch digging machines; the present application being a division of.my-.-allowed application, Serial No. 445,364, filed July 23, 1954, now Patent No. 2,763,941, issued September 25, 1956, on Ditch Forming Machine.

Such machine includes a digging structure and independently operable sidetraction unitswhich both sup port the structure and move the same along the ground.

The principal object ofthis invention is to employ a poweriplant to drive the digging. structure, and-independent power units to drive the traction units. In this manner separate control of the speed of operation of the digging structure and of the traction elements may be more easily effected than would otherwise be the case, and the entire power of the power plant may be utilized to operate the digging structure without starving the traction elements and thus affecting the forward speed of the machine, and vice versa.

A further object of the invention is to arrange the independent power units directly on the traction units and mechanically separate from each other, so that the power units may drive the traction units without'the need of any relatively complicated gearing or similar mechanism between the transversely spaced power units themselves, or between each power unit and the corresponding traction unit. In this manner, the traction units may be driven straight ahead or back at the same speed, or either power unit and the corresponding traction unit stopped or even backed up, so as to steer the machine.

A further object of the invention is to provide electric motors as the driving means of the power units, and to provide a single current generating unit on the machine, supplying current equally to both motors, so that both traction units are driven with equal power at all times.

Still another object of the invention is to provide a practical, reliable, and durable drive mechanism for selfpropelled implements, and one which will be exceedingly effective for the purpose for which it is designed.

These objects are accomplished by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the drawings:

Fig. 1 is a side elevation of the machine with the digging structure.

Fig. 2 is a top plan view of the machine, somewhat diagrammatic and with certain parts omitted and others in section.

Referring now more particularly to the drawings, and to the characters of reference marked thereon, the machine includes a main frame, indicated generally at 1, which supports the usual housedpower plant, indicated at 2, and which drives a transmission enclosed in a housing 3 and from which a driven transverse shaft 4 projects. The digging structure includes a rearwardly projecting boom 5 pivotally supported on frame 1, andv which boom United States Patent 2,853,810 *Patemd sept- 30.19.58

carries an endless digging unit, indicated generally at.6, and which is suitably driven from the transverse-shaft 4 by chain drives 4a.

The digging structure per se and the-specific'mannerof driving the same form no part of the present invention, and "all are fully described in said allowed-application, Serial No. 445,364; now Patent No. 2,763,941.

' The frame 1 includes longitudinally spaced, transverse frame beams 7 projecting laterally out some distance, and connected at their outer end to and rigidly supporting endless traction units 8 of generally conventional form, and which support the machine from the ground, and by means of which the machine is advanced or steered, as may be desired.

The means for thusv driving and steering the traction units, and which is the subject matter of this invention,.is

constructed and arranged as follows:

Mounted on top of each traction unit 8, and practically forming a part thereof is a rigid platform 9, extending lengthwise of said unit. Mounted on this platform-intermediate its .end'sis a reversible electric motor 10 which drives a transmission unit .11 which includes an upstanding operating lever 12 disposed within reach of the operator of the machine from his .seat 13 thereon.

The output shaft '14 of thetransmission unit 11 is connected by suitable means, such as a chain drive 15, to the input shaft 16 of a housed Worm and gear unit 17 whichas well as the transmission unit 11is rigidly mounted on platform 9.

The output shaft 18 of unit 17 extends beyond the side edges of the platform and traction unit, and sprockets 19 are fixed on the ends of said shaft in alinement with other larger sprockets 20 secured on the ends of the shaft 21 of the rear sprocket of the endless traction unit 8; the corresponding sprockets being connected by endless chains 22.

It Will thus be seen that by reason of the speed-reducing effect obtained by the worm and gear unit, in addition to the relatively small and large sprockets embraced by chains 22, ample power is obtained for the desired slow advance of the machineeven when under load without necessitating the use of excessively large motors 10.

Power for both motors 10 is obtained from an electric generator 23 mounted on one platform 9 ahead of the adjacent motor 10; the generator being driven by an internal combustion engine having an output shaft 24 and mounted on the platform 9 within a suitable housing 25. The generator is of sufficient capacity to fully feed both motors 10; the Wiring and control elements between the generator and motors being omitted from the showing, since they may be of any suitable type, and form no part of this invention.

It is to be noted that the transmission 11 is for speed changes only; reversal of the direction of travel of the endless track units being effected by reversing the motors 10, the circuits of which are separate from each other and arranged so that the motors may be separately controlled. Such circuits therefore include separate switches selectively operable by the machine operator from his seat.

It will thus be seen that to steer the machine it is only necessary to deenergize-or reverseone motor or the other, and no clutches or the like are required in the drives between the motors and the endless traction units.

By reason of the sprocket shaft 21 of each traction unit being driven from both ends, a balanced drive is obtained, and torque strains on said shaft are minimized.

Since each traction unit 8 has its individual drive means mounted in unitary connection therewith, and without any mechanical connection with the frame 1, it is possible to easily change the gauge of the traction units, as the requirements of any particular purchaser may dictate, merely by putting in longer or shorter frame beams 7, as may be needed.

From the foregoing description it will be readily seen that there has been produced such a device as will substantially fulfill the objects of the invention, as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still'in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described the invention, the following is claimed as new and useful, and upon which Letters Patent are desired:

1. In combination, a main frame, a ground working structure supported from the frame, traction units supporting the frame from the ground for movement along frame from the ground to the sides of the structure, and each including a transverse drive shaft, a platform supported from and superimposed on each unit, an electric motor on the platform intermediate its ends and extending axially lengthwise thereof, a change-speed transmissionv on the platform to which the motor is directly connected, a worm and gear unit on the platform to the worm of which the transmission is connected in driving relation and including a transverse shaft projecting from the gear of said unit parallel to the first named shaft, and a speedreducing drive connection between the shafts at each end thereof.

References Cited in the file of this patent UNITED STATES PATENTS 584,323 Bunnell June 15, 1897 1,232,629 Wade July 10,1917 1,391,529 Crochat- Sept. 20, 1921 1,407,969 Wickersham Feb. 28, 1922 1,863,504 Schmid June 14, 1932 2,259,659 Penote et al Oct. 21, 1941 2,311,834 Hollmann et al Feb. 23, 1943 2,592,023 Gleason Apr. 8, 1952 2,605,852 Rhoads Aug. 5, 1952 2,641,070 Bennett June 9, 1953 2,642,984 Mercier June 23, 1953 2,787,331 LeTourneau et al Apr. 2, 1957 FOREIGN PATENTS 825,962 France. Dec. 27, 1937 

